Search spammers (or web spammers) spam web users via techniques that cause search engines to rank their links, undeservedly, amongst top search results. Search spammers typically target commerce search queries that include keywords of well-known brands, high demand consumer products, etc. For example, spam targeted keywords include generic terms such as handbag and ringtone as well as trademarks such as GUCCI® and VIAGRA®. As most search spammers spam for profit, certain consumer product sellers bear a disproportionate burden of illicit search spam activity. Further, search spam places a burden on the web. Search spam traffic can be significant and search spam decreases search efficiency. In addition, search spammers divert advertising money from legitimate advertising service providers. Search spammers free ride on the goodwill of-web and act counter to the web's intended experience.